Evaluation of External Costs Change Due to High Speed Rail in Italy

The evaluation of the external costs of transport has become increasingly relevant and fundamental, as much as the growing interest and concern about climate change; even if these costs involve aspects beyond environmental ones, like accidents and congestion, they allow the environmental impacts of people's transport choices to be determined and represented, transforming them in monetary costs. The EU Commission has been debating these topics for almost 20 years, and DG Move has covered this topic in the Handbook on the External Costs of Transport; moreover, during this period (2022-2024), the European Commission has been organising a fitness check to prepare a recommendation on how to better implement the polluter pays principle, which could balance the costs perceived by the polluters and those borne by the community. In this context, railways can play a key role in reducing the impact of Transport. It is well-known that train transport is one of the least impactful modes of transport, as showed by several studies, like that conducted by UIC "Greening Transport" (Domergue & Markovic-Chenais, Greening transport-Reduce external costs, 2012); it could be improved by new technologies, but it is already less impactful than air and road transport. The problem is encouraging its use by passengers and freight carriers. For instance, users of the roads don't perceive all of the effects and the relative costs that they produce: for them, travel by car remains the most convenient mode in terms of money, comfort, and (perhaps even) time. Only major events, like an economic crisis or a pandemic, can change people's mobility habits, and this change will not always favour less impactful modes of travel, as we saw during the COVID-19 pandemic. Some governments have sought to resolve this through modal choice: France, for example, has sought to reduce its environmental impacts (namely CO2 emissions) by banning air connections where comparable train services exist, and take less than two and a half hours to cover the OD distance. Despite the foregoing, and even if modal choices in Italy haven't changed much over the past few decades, some Italian Origin/Destination pairings witnessed major changes in people's modal choices following the development of High Speed Rail. Based on this modal shift, this paper aims to analyse the change in the External Impacts of Transport for passengers on certain HSR OD pairings in Italy. The comparison is performed between the external costs of transport with or without the High Speed Rail services. The analysis is carried out considering the modal share surveys and pax-km for the specific OD pairing selected for the years 2008 and 2019. The external costs evaluation follows the methodology explained in the Handbook on the External Costs of Transport by DG MOVE (EC [European Commission] et al., Handbook on the external costs of transport-Version 2019-1.1, 2020).